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R. Tesser et al.
the oil-dispersed phase [122]. Moreover, the use of EO can induce modifications in
terms of film transparency and colour [122] and this represents a serious drawback
because of the appearance of the coatings is of relevance since their commercial
acceptance depends mainly on this attribute. This modification has been attributed
to the migration of EOs dispersed droplets to the external surface of the film during
film drying, which leads to surface irregularities. Nevertheless, observed differences
in terms of colour are not significant when low concentrations of EOs are used in
bioactive films [122] so a key point to be tuned is the EO concentration.
Despite the interesting properties and possibilities offered by edible packagings
for improving the shelf life of the foodstuff, few industrial applications were developed [52] as the formulation of these materials still remains empirical and uneasy.
Edible packagings are an integral part of food as they are located on the food surface
or as thin layers between several parts within the product. Nowadays in the European Community, there is no regulation that specifies how edible packaging could
be classified [13]. As in most cases, edible packagings do not provide a significative nutritional value to the coated food, it is a general opinion that they should be
considered more like an additive than an ingredient.
8.3.4.2 Type of Antimicrobial Packaging
A new generation of food packaging may include materials with inherent antimicrobial properties and can be classified, in this case, as ‘active packagings’. These
innovative packaging technologies could play a key role in extending the shelf life
of foods and reduce the risk of pathogens. Active packaging can interact with the
product through the headspace between the package and the food system to realize
the desired effect [31, 118, 181].
From a general point of view, active antimicrobial/antifungal packagings can be
configurated in several forms such as [13]:
1. Addition of capsules containing volatile antimicrobial agents into packages.
The most successful application of this strategy consisted in adding sachets
containing, for example, oxygen of moisture absorbers or ethanol generators
[89, 181].
2. Incorporation of volatile and non-volatile antimicrobial agents directly into polymeric matrix. This possibility has been commercially applied in drug and pesticide delivery, textiles, surgical implants and other biomedical devices. Few
food-based applications appeared on a market scale [13]. Moreover, ‘natural’
antimicrobials agents have been incorporated into paper, thermoplastics and thermosets, and have been tested against a variety of microorganisms including Listeria monocytogenes, pathogenic E. coli and spoilage organisms. Among all the
antimicrobials, silver-substituted zeolites are the most widely used as polymer
additives for food applications, especially in Japan [31].
3. Coating or adsorbing antimicrobials onto polymer surfaces. As an applicative
example of this possibility, we can cite the incorporation of fungicides into waxes
R. Tesser et al.
the oil-dispersed phase [122]. Moreover, the use of EO can induce modifications in
terms of film transparency and colour [122] and this represents a serious drawback
because of the appearance of the coatings is of relevance since their commercial
acceptance depends mainly on this attribute. This modification has been attributed
to the migration of EOs dispersed droplets to the external surface of the film during
film drying, which leads to surface irregularities. Nevertheless, observed differences
in terms of colour are not significant when low concentrations of EOs are used in
bioactive films [122] so a key point to be tuned is the EO concentration.
Despite the interesting properties and possibilities offered by edible packagings
for improving the shelf life of the foodstuff, few industrial applications were developed [52] as the formulation of these materials still remains empirical and uneasy.
Edible packagings are an integral part of food as they are located on the food surface
or as thin layers between several parts within the product. Nowadays in the European Community, there is no regulation that specifies how edible packaging could
be classified [13]. As in most cases, edible packagings do not provide a significative nutritional value to the coated food, it is a general opinion that they should be
considered more like an additive than an ingredient.
8.3.4.2 Type of Antimicrobial Packaging
A new generation of food packaging may include materials with inherent antimicrobial properties and can be classified, in this case, as ‘active packagings’. These
innovative packaging technologies could play a key role in extending the shelf life
of foods and reduce the risk of pathogens. Active packaging can interact with the
product through the headspace between the package and the food system to realize
the desired effect [31, 118, 181].
From a general point of view, active antimicrobial/antifungal packagings can be
configurated in several forms such as [13]:
1. Addition of capsules containing volatile antimicrobial agents into packages.
The most successful application of this strategy consisted in adding sachets
containing, for example, oxygen of moisture absorbers or ethanol generators
[89, 181].
2. Incorporation of volatile and non-volatile antimicrobial agents directly into polymeric matrix. This possibility has been commercially applied in drug and pesticide delivery, textiles, surgical implants and other biomedical devices. Few
food-based applications appeared on a market scale [13]. Moreover, ‘natural’
antimicrobials agents have been incorporated into paper, thermoplastics and thermosets, and have been tested against a variety of microorganisms including Listeria monocytogenes, pathogenic E. coli and spoilage organisms. Among all the
antimicrobials, silver-substituted zeolites are the most widely used as polymer
additives for food applications, especially in Japan [31].
3. Coating or adsorbing antimicrobials onto polymer surfaces. As an applicative
example of this possibility, we can cite the incorporation of fungicides into waxes